I Swiftcast Raise frequently, and I don't think I've ever seen a cast bar at all. The only time I ever had a swiftcast skill 'interrupted' was when another WHM Swiftcast Raised someone about a quarter second before I did. My animation started, but the Raise didn't go through because someone else had already used Raise on the dead guy. Even with this interrupted cast, though, I was still able to insta-cast Medica II immediately afterwards (the Swiftcast didn't get used up by the failed Raise), so I'm not really sure what's going on with your scenario.